not in things themselves provoked by the frequencies of light emitted or reflected by things
TRANSCRIPT
Light & ColorLight Part 3
Color
Not in things themselves
Provoked by the frequencies of light emitted or reflected by things
Newton
Studied colors created by passing sunlight through a prism
Newton
White Light under which white objects appear white and colored objects appear in their individual colors
ie: Sunlight
White is the combination of all of the colors of light, but not a color itself
Black is also not a color, but instead the absence of light
Colors of Objects
Due to the way the objects reflect light
As light strikes an object the electrons in the object are forced into vibrations
Once vibrating these electrons send out their own energy waves in all directions
Colors of Objects
If the vibrations are at resonant frequencies light is absorbed
If the vibrations are above or below resonant frequency light is re-emitted or passes back into the medium from which it came (reflection)
Objects can only reflect frequencies of light which are present in the illuminating light
The Sun
Brighter in mid-frequency yellow & green regions
Higher and Lower frequencies are less bright
Reason yellow and bright red vehicles stand out
Mixing Colored Light
Red low frequency Green middle frequency Blue high frequency Red + Green + Blue White
Any color can be made by overlapping these three colors and adjusting the brightness of each
Mixing Colored Light
Red + Blue Magenta
Red + Green Yellow
Blue + Green Cyan
Complementary Colors
Any two colors of light that when added together produce white light
Blue + Yellow White Red + Cyan White Green + Magenta White
Pigments
Mixing pigments or dyes does not produce the same effect as mixing colored light
Are materials that selectively absorb colored light
Why is the sky blue?
Scattering of light by the particles in our atmosphere causes the particles to vibrate
During the day light takes a shorter path through the atmosphere causing the particles to vibrate at a higher frequency
Why are sunsets red?
During sunrise and sunset the light from the sun takes a longer path through the atmosphere
This now causes the scattered light to vibrate at a lower frequency